Final answer:
To represent the situation with an equation, we express the cost of each submarine as 'x' and the total cost of pitchers of pop as 'P', leading to the equation 6x + P = $63.85. Additional information is required to find specific values for 'x' and 'P'.
Step-by-step explanation:
To write an equation to represent the situation where a group of 6 friends goes to a restaurant, orders 3 pitchers of pop, each person orders a submarine, and the total bill is $63.85, you would start by identifying the unknown variable and the constants.
Let's assume the cost of each submarine is 'x' dollars and the total cost of the 3 pitchers of pop is a constant value which we can call 'P'. There are 6 friends, so they order 6 submarines in total. The equation would look like:
6x + P = $63.85
We only have one equation but two unknowns; therefore, additional information is needed to solve for 'x' or to determine 'P', the cost of the pitchers of pop.